Researchers led by Dr Woon-Puay Koh from the Duke-NUS Graduate Medical School Singapore and the National University of Singapore (Chow et al.) also found that black and green tea, fruit juice and soft drinks did not increase the risk of cirrhosis mortality.
But in line with previous studies, Koh and her team found that heavy alcohol use increased the risk of death.
“Since coffee is widely consumed globally, it [the study] has significant clinical and public health implications and provides further impetus to evaluate coffee as a potential therapeutic agent in patients with chronic liver diseases…” Chow et al. conclude.
A 2004 World Health Organization (WHO) report estimated that 800,000 deaths worldwide are caused by liver cirrhosis each year, with 170,000 deaths in Europe alone linked to the disease.
The Singapore Chinese Health Study
Using a prospective population-based study, The Singapore Chinese Health Study, Chow et al. recruited 63,275 Chinese subjects aged 45-74 who were gave data on their diet, lifestyle and medical history during interviews during 1993 and 1998.
Subjects were followed for the next 15 years on average, during which time 14,928 (24%) died. 114 deaths were due to liver cirrhosis, 33 (29%) caused by viral hepatitis B, 14 (12%) due to alcohol-related cirrhosis (12%) and two (2%) from hepatitis C.
Koh et al. found that people who drank at least 20g of ethanol daily were at greater risk of cirrhosis mortality but associated coffee intake with a lower risk of death – specifically for non-viral hepatitis related cirrhosis.
The team say that patients who died from non-viral hepatitis-related cirrhosis in the current study were older and more likely to be diabetic or be overweight than the rest of the subjects – which is consistent with the characteristics seen in patients with NAFLD (non-alcoholic fatty liver disease).
Subjects who drank 2+ cups of coffee daily had a 66% reduction in mortality risk compared to non-daily coffee drinkers, but intake was not found to lower the risk of death due to viral Hepatitis B-related cirrhosis.
‘Westernizing lifestyles’ changing Asia
Koh claimed her team’s study was the first to show a difference between the effects of coffee on non-viral and viral hepatitis related cirrhosis mortality, and said its positive effects could be due to the drink’s antioxidant and anti-inflammatory properties.
She added its findings resolved apparently conflicting results on the effect of coffee in Western and Asian based studies of deaths from hepatitis-related cirrhosis more generally.
“Our findings suggest that while the benefit of coffee may be less apparent in the Asian population where chronic viral hepatitis B currently predominates, this is expected to change…” Koh said.
She pointed to an expected increase in rates of non-viral hepatitis related cirrhosis in Asia, due to increasing affluence and westernizing lifestyles among younger people.
Title: ‘Coffee, Alcohol and Other Beverages in Relation to Cirrhosis Mortality: The Singapore Chinese Health Study’
Authors: Goh, G.B-B, Chow, W-C., Wang, R., Yuan, J-M., Koh, W-P.
Source: Hepatology, 2014, doi:10.1002/hep.27054